This invention relates to a novel method and apparatus for securing ceramic fiber blanket insulation linings to the interior walls of a process vessel which has the result of improving their overall reliability and serviceability within the reactor environment. The invention makes possible the replacement of castable refractory linings in the domed head portions of cold shell reactors. Typically, in the dome of such reactor vessels, it has been conventional to secure castable refractory thereto by the use of welded steel anchors to the interior wall of the shell and the application of castable refractory thereover. When such castable refractory linings require repair due to breakdown of the insulation properties of the lining system, considerable time and expense is consumed. Lining repairs typically involve the shut-down of the unit, cool-down, dumping of catalyst, building of scaffolding within the process vessel, jackhammer removal of the failed refractory and repair of the shell and anchors and reapplication of castable refractory. Completion of these steps usually requires at least 72 hours. Thereafter, the newly applied castable refractory would additionally require approximately 24 hours for curing, as much as 36 hours for dry-out and inspection thereafter before the unit could be brought back into service. Obviously, therefore, it is very desirable and an object of the present invention to provide a new and novel insulation attachment system for ceramic blanket-type insulation which may be readily applied to the domed head or bottom portions of a cylindrical reactor shell much more readily than the previously described conventional technique of lining these portions with castable refractory secured to the shell through the use of intermediate welded steel anchors.